VAT Invoice Requirements for SaaS by Country: EU, UK, UAE, KSA, Japan

SaaS invoices look similar at a glance but diverge sharply in what each jurisdiction requires. Miss a mandatory field and your customer's input VAT claim can be denied; mis-state the reverse charge narrative and the whole invoice can be rejected. This guide compares the five jurisdictions that generate the most invoice-related disputes for SaaS companies: the EU, UK, UAE, Saudi Arabia, and Japan.

European Union (Directive 2006/112/EC, Articles 226–231)

The EU VAT Directive sets a harmonised minimum for invoice content, transposed by each Member State. Under Article 226, a full VAT invoice must contain:

• Date of issue
• A sequential number that uniquely identifies the invoice
• Supplier's name, address, and VAT identification number
• Customer's name, address, and (for B2B) VAT identification number
• Quantity and nature of the goods or services
• Date of supply (if different from invoice date)
• Taxable amount per VAT rate or exemption
• VAT rate applied
• VAT amount in euro (or national currency)
• Where applicable: the mention "Reverse charge" (Article 226(11a))
• Where applicable: reference to exemption provision

Simplified invoices (Article 220a)

Member States may permit simplified invoices for amounts up to €100 (or €400 in limited cases). Simplified invoices can omit customer details and some line-level information but must still show supplier details, invoice date and number, description of supply, VAT amount, and VAT rate.

Reverse charge narrative

Cross-border B2B SaaS invoices must carry the reverse charge mention. Examples accepted by most Member States:

• "Reverse charge"
• "Reverse charge — VAT to be accounted for by the recipient"
• "Reverse charge — Article 196 of Council Directive 2006/112/EC"

See our article on reverse charge VAT for the mechanics.

E-invoicing and ViDA

From July 2030, the EU's ViDA package mandates structured e-invoicing for cross-border B2B. Several Member States already require domestic e-invoicing today: Italy (SDI), France (PDP mandate phasing 2026–2027), Germany (from 2025 for B2B receipt, 2027–2028 for issuance), Poland (KSeF), Spain (VeriFactu). Format is typically UBL or CII with local envelope.

United Kingdom (VAT Regulations 1995, Regulation 14)

Post-Brexit, UK invoice rules mirror the EU's pre-Brexit requirements but are owned by HMRC. A full UK VAT invoice must show:

• An identifying sequential number
• Invoice date and tax point (if different)
• Supplier's name, address, and VAT registration number
• Customer's name and address (and VAT number for reverse charge)
• Description of the goods or services
• Quantity or extent of supply
• Rate of VAT
• Amount per rate and total charge, both exclusive and inclusive of VAT
• Total VAT payable in sterling

Reverse charge narrative (UK)

For supplies where the UK customer will account for VAT, HMRC accepts any narrative that makes the reverse charge clear, e.g., "Reverse charge: Customer to pay the VAT to HMRC" or "VAT to be accounted for by the recipient under the reverse charge."

Currency

Invoices can be in any currency, but the UK VAT amount must be stated in sterling. The exchange rate should be the rate on the tax point date, drawn from a consistent source (HMRC published rates, ECB reference rates, or the customer's bank rate).

Storage

Invoices must be kept for six years under Making Tax Digital. Electronic storage is acceptable if images are readable and searchable.

United Arab Emirates (Federal Decree-Law 8/2017, Executive Regulation)

A UAE tax invoice must display, per Article 59 of the Executive Regulation:

1. The words "Tax Invoice" clearly displayed
2. Supplier name, address, and TRN
3. Recipient name and address (and TRN if registered)
4. Invoice date
5. A sequential invoice number
6. Date of supply (if different from invoice date)
7. Description of goods or services
8. Unit price, quantity, and net amount (in AED or with AED equivalent)
9. Rate of VAT and VAT amount
10. Total invoice amount
11. For zero-rated or exempt supplies: the relevant notation
12. For reverse charge: statement that the supply is subject to reverse charge under Article 48

Simplified tax invoice: For B2C supplies under AED 10,000, a simplified format without recipient details is permitted but must still include the words "Tax Invoice," supplier TRN, date, description, VAT amount, and total.

Saudi Arabia (KSA — ZATCA Fatoora e-invoicing)

Saudi Arabia operates a two-phase e-invoicing regime mandated by the Zakat, Tax and Customs Authority (ZATCA):

• Phase 1 (Generation phase, since December 2021): All VAT-registered taxpayers must generate and store electronic tax invoices (e-invoices) in XML or PDF/A-3 with embedded XML.
• Phase 2 (Integration phase, waves since January 2023): Integration with ZATCA's Fatoora platform for real-time clearance of B2B invoices and reporting of B2C invoices within 24 hours.

Mandatory content:

• Supplier name, address, VAT registration number
• Customer name, address, VAT number (B2B only)
• Unique Invoice Identifier (UUID)
• QR code (mandatory on all e-invoices since Phase 1)
• Date of issue and date of supply
• Description of supply
• Net amount, 15% VAT rate, VAT amount, gross total (in SAR)
• For B2B: Cryptographic Stamp Identifier (CSID) issued by ZATCA in Phase 2
• For reverse charge or zero-rated: required narratives

Japan (Consumption Tax Act, qualified invoice system)

Since 1 October 2023, Japanese qualified invoices (tekikaku seikyusho) must include:

1. Name of the Qualified Invoice Issuer (supplier)
2. Registration number in the format T + 13 digits (e.g., T1234567890123)
3. Transaction date
4. Description of goods or services
5. Taxable value per applicable rate (10% standard or 8% reduced)
6. Applicable tax rate(s)
7. Amount of consumption tax per rate
8. Recipient name

Invoices can be issued in English or in Japanese; bilingual invoices are common. The T-number formatting must be exact — no hyphens, spaces, or lowercase t — or the Japanese customer's input credit claim can be denied. See our full Japan JCT guide.

Cross-country differences at a glance

• Invoice label: The EU does not require a specific label; the UK accepts any invoice; the UAE requires the words "Tax Invoice"; KSA requires "Tax Invoice" plus QR code; Japan requires the Qualified Invoice Issuer's T-number in the prescribed format.
• E-invoicing: KSA is the most demanding with real-time clearance. Italy, France, Germany, and Poland follow. The EU as a whole moves to mandatory cross-border e-invoicing by 2030 under ViDA.
• Currency: All five jurisdictions allow foreign-currency invoices but require the VAT amount in local currency: euro (or national), sterling, AED, SAR, yen.
• Retention: EU ten years (OSS) or national minimum; UK six years; UAE five years; KSA six years; Japan seven years.
• Reverse charge narrative: Harmonised in the EU ("Reverse charge"); UK flexible; UAE references Article 48; Japan does not use reverse charge on the invoice itself for the B2B electronic services regime, but the Japanese customer self-assesses.

Common mistakes

1. Omitting the VAT amount in local currency. All five jurisdictions require the tax amount in local currency.
2. Missing reverse charge wording. Article 226(11a) requires it; absence can invalidate the buyer's treatment.
3. Wrong T-number format in Japan. Must be T + 13 digits, no separators.
4. Missing QR code on KSA invoices. ZATCA rejects non-compliant invoices in Phase 2 integration.
5. Non-sequential invoice numbering. All five jurisdictions require sequential, unique numbering.
6. Using stale VAT rates. Apply the rate in force on the tax point date, not the contract date.

Recommended pattern for global SaaS

A single invoice template with parameterised fields can meet all five regimes if it:

• Pre-fills "Tax Invoice" when the customer country requires it.
• Pulls the supplier's tax ID from a country-specific mapping (VAT number, TRN, T-number).
• Renders the appropriate reverse charge narrative in the right language.
• Includes the QR code for KSA.
• Stores the structured XML for e-invoicing jurisdictions.

This is the design pattern DeterminedAI uses internally: a canonical invoice object plus country-specific renderers.